A Trial of the Safety and Efficacy of SEP-363856 in the Treatment of Adults With Major Depressive Disorder
A Phase 2/3, Multicenter, Randomized, Double-blind, Placebo-controlled Trial of the Safety and Efficacy of Flexible Doses of SEP-363856 as Adjunctive Therapy in the Treatment of Adults With Major Depressive Disorder
1 other identifier
interventional
929
7 countries
77
Brief Summary
Demonstrate ability of SEP-363856 to be superior to placebo as an adjunctive therapy to ADT in change from baseline in depressive symptoms (MADRS \& CGI-S) in MDD patients who had an inadequate response to prior ADT therapy.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_2 major-depressive-disorder
Started Nov 2022
Typical duration for phase_2 major-depressive-disorder
77 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
October 10, 2022
CompletedFirst Posted
Study publicly available on registry
October 25, 2022
CompletedStudy Start
First participant enrolled
November 9, 2022
CompletedPrimary Completion
Last participant's last visit for primary outcome
November 6, 2025
CompletedStudy Completion
Last participant's last visit for all outcomes
November 13, 2025
CompletedFebruary 18, 2026
November 1, 2025
3 years
October 10, 2022
February 13, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Montgomery Åsberg Depression Rating Scale (MADRS)
Change from the baseline to the Montgomery Åsberg Depression Rating Scale (MADRS) total score. The Montgomery Åsberg Depression Rating Scale consists of 10 items, each rated from 0 to 6 (for a total score of 0 to 60). A higher score represents a higher severity of the level of depression.
From baseline to week 14
Secondary Outcomes (1)
Clinical Global Impression - Severity of Illness (CGI-S)
From baseline to week 14
Study Arms (2)
SEP-363856 & ADT (Antidepressant Therapy)
EXPERIMENTALPlacebo & ADT (Antidepressant Therapy)
PLACEBO COMPARATORInterventions
Eligibility Criteria
You may qualify if:
- Male and Female subjects between 18-65 years of age, with a primary diagnosis of major depressive disorder and in a current major depressive episode
- Current major depressive episode must be at least 8 weeks and no longer than 2 years in duration
- History of an inadequate response to at least 1 and no more than 3 antidepressant treatments in the current major depressive episode
You may not qualify if:
- Subjects who report an inadequate response to more than 3 antidepressant treatments in the current episode
- Subjects with a lifetime history of schizophrenia spectrum or other psychotic disorder, bipolar or related disorder, major or mild neurocognitive disorder, neurodevelopmental disorder of greater than mild severity or of a severity that impacts the participant's ability to consent/ follow study directions/ or otherwise safely participate in the study, borderline or antisocial personality disorder.
- Subjects with a current diagnosis of post-traumatic stress disorder, obsessive compulsive disorder, panic disorder, or eating disorder (including anorexia nervosa or bulimia).
- Sexually active subjects, who could become pregnant, not agreeing to practice 2 sponsor approved methods of birth control or remain abstinent during the trial and for 30 days (females) or 90 days (males) after last dose of study drug.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (77)
University of Alabama at Birmingham
Birmingham, Alabama, 35294, United States
Scottsdale Clinical Research
Scottsdale, Arizona, 85260, United States
DelSol Research
Tucson, Arizona, 85715, United States
Pillar Clinical Research
Bentonville, Arkansas, 72712, United States
ProScience Research Group
Culver City, California, 90230, United States
Wr-Pri, Llc
Encino, California, 91316, United States
Collaborative NeuroScience Research , LLC
Garden Grove, California, 92845, United States
Alliance Research
Long Beach, California, 90807, United States
ATP Clinical Research, Inc.
Orange, California, 92868, United States
Anderson Clinical Research
Redlands, California, 92374, United States
California Mental Behavioral Health
Santee, California, 92071, United States
Schuster Medical Research Institute SMRI
Sherman Oaks, California, 91403, United States
Viking Clinical Research
Temecula, California, 92591, United States
Collaborative Neuroscience Research LLC
Torrance, California, 90504, United States
Sunwise Clinical Research with is in Lafayette, CA
Walnut Creek, California, 94596, United States
Institute of Living Hartford Hospital
Hartford, Connecticut, 06106, United States
Clinical Neuroscience Solutions Inc.
Jacksonville, Florida, 32256, United States
K2 Medical Research
Maitland, Florida, 32751, United States
Central Miami Medical Institute
Miami, Florida, 33125, United States
Clinical Neuroscience Solutions Inc. dba CNS Healthcare
Orlando, Florida, 32801, United States
Combined Research Orlando Phase I-IV
Orlando, Florida, 32807, United States
K2 Medical Research
Tampa, Florida, 33607, United States
Interventional Psychiatry of Tampa Bay
Tampa, Florida, 33629, United States
Advanced Discovery Research LLC
Atlanta, Georgia, 30318, United States
Renew Health Clinical Research
Snellville, Georgia, 30078, United States
MetroMed Clinical Trials
Chicago, Illinois, 60614, United States
AMR Convention Research
Warrenville, Illinois, 60555, United States
Benchmark Research
Shreveport, Louisiana, 71101, United States
Cenexel CBH (CBH Health)
Gaithersburg, Maryland, 20877, United States
Copley Clinical
Boston, Massachusetts, 02116, United States
Boston Clinical Trials
Roslindale, Massachusetts, 02131, United States
Adams Clinical
Watertown, Massachusetts, 02471, United States
Vitalix Clinical
Worcester, Massachusetts, 01608, United States
Neurobehavioral Medicine Group
Bloomfield Hills, Michigan, 48302, United States
Precise Research Centers
Flowood, Mississippi, 39232, United States
Center for Emotional Fitness
Cherry Hill, New Jersey, 08002, United States
Integrative Clinical Trials
Brooklyn, New York, 11229, United States
Basil Clinical
Inwood, New York, 11096, United States
Berman Clinical
New York, New York, 10029, United States
Manhattan Behavioral Medicine PLLC
New York, New York, 10036, United States
The Medical Research Network, LLC
New York, New York, 10128, United States
Patient Priority Clinical Studies LLC
Cincinnati, Ohio, 45215, United States
The Ohio State University
Columbus, Ohio, 43210, United States
Sooner Clinical Research
Oklahoma City, Oklahoma, 73116, United States
Suburban Research Associates
West Chester, Pennsylvania, 19380, United States
Clinical Neuroscience Solutions Inc.
Memphis, Tennessee, 38119, United States
Donald J. Garcia, Jr., MD, PA
Austin, Texas, 78737, United States
Community Clinical Research, Inc.
Austin, Texas, 78754, United States
FutureSearch Trials of Dallas
Dallas, Texas, 75251, United States
North Texas Clinical Trials
Fort Worth, Texas, 76104, United States
DM Clinical Research - Belliare
Houston, Texas, 77081, United States
Psychiatric And Behavioral Solutions, LLC
Millcreek, Utah, 84124, United States
Core Clinical Research
Everett, Washington, 98201, United States
Diagnostic Consultive Center Higya AD
Pazardzhik, 4400, Bulgaria
Ambulatory for Group Practice for Specialized Psychiatrics Help PHILIPOPOLIS OOD
Plovdiv, 4002, Bulgaria
Medical Center Sveti Naum
Sofia, 1113, Bulgaria
DCC-Mladost M OOD
Varna, 9020, Bulgaria
Mental Health Center Vratsa
Vratsa, 3000, Bulgaria
Chatham-Kent Clinical Trials Research Centre
Chatham, Ontario, N7L 1C1, Canada
Institute of Mental Health Research IMHR
Ottawa, Ontario, K1Z 7K4, Canada
Centre for Addiction and Mental Health (CAMH & University of Toronto)
Toronto, Ontario, M6J 1H4, Canada
BRAIN-SOULTHERAPY s.r.o.
Kladno, Central Bohemia, 272 01, Czechia
A-Shine s.r.o.
Ptzen, Plzeň Region, 30100, Czechia
National Institute of Mental Health
Klecany, 25067, Czechia
Clintrial s.r.o.
Prague, 10000, Czechia
Velocity Clinical Research Wiesbaden
Wiesbaden, Hesse, 65189, Germany
Pharmakologisches Studienzentrum Chemnitz GmbH
Chemnitz, MA, 09111, Germany
Private Practice Kusserow
Stralsund, Mecklenburg-Vorpommern, 18439, Germany
Somni Bene Institut for Medical Research
Schwerin, Mecklenburg, 19053, Germany
Arztepartnerschaft Dr. med. J. Springhub/ W. Schwarz-Studienzentrum Nord-West
Westerstede, 26655, Germany
ClinExpert Kft.
Budapest, 1033, Hungary
Semmelweis University
Budapest, M6J 1H4, Hungary
Praktyka Lekarska Malgorzata Wojtanowska-Bogacka
Poznan, Greater Poland Voivodeship, 60-192, Poland
Osrodek Badan Klinicznych CLINSANTE
Bydgoszcz, Kuyavian-Pomeranian Voivodeship, 85-794, Poland
MlynowaMed - Bialystok
Bialystok, OH, 15-404, Poland
Centrum Medyczne Luxmed Sp.z. o.o.
Lublin, 20-109, Poland
Indywidualna SpecjalistycznaPraktyka Lekarska AgnieszkaRemlinger-Molenda
Szkolkarska 32, 62-002, Poland
Related Links
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Study Design
- Study Type
- interventional
- Phase
- phase 2
- Allocation
- RANDOMIZED
- Masking
- SINGLE
- Who Masked
- PARTICIPANT
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
October 10, 2022
First Posted
October 25, 2022
Study Start
November 9, 2022
Primary Completion
November 6, 2025
Study Completion
November 13, 2025
Last Updated
February 18, 2026
Record last verified: 2025-11
Data Sharing
- IPD Sharing
- Will share
- Shared Documents
- STUDY PROTOCOL, SAP, ICF
- Time Frame
- Data will be available after marketing approval in global markets, or beginning 1-3 years following article publication. There is no end date to the availability of the data.
- Access Criteria
- Otsuka will share data on the Vivli data sharing platform which can be found here: https://vivli.org/ourmember/Otsuka/
Anonymized Individual participant data (IPD) that underlie the results of this study will be shared with researchers to achieve aims pre-specified in a methodologically sound research proposal. Small studies with less than 25 participants are excluded from data sharing.